The invention relates to a color measurement system and more particularly to a color measurement system for color measurement of cooled product after the product has been extruded by an extrusion mechanism.
In the manufacturing of some materials, for example, polymeric materials, the product undergoes several manufacturing processes before the final product is created. These processes can be performed in one processing area or at several processing areas. In either case, the product is transported from process to process, or the product is transported to a finishing area. In addition, at the final processing area the product can be formed into various shapes and sizes. Typically, the movement and final forming of the product is accomplished by extruding the material through a conduit. Heating the product so that the product flows similar to a liquid facilitates the extrusion of the product through the conduit.
Many processes, especially the finishing process and forming, desire to identify or measure the color of the cooled product. Color identification and measurement is desired for, among other things, determining the state of the process, determining the quality of the product and sorting the product. However, the heated product can have a different color than the cooled product. In one example, color of the product is identified and measured by directing a sample of the product to a bypass section in the conduit or main extruder. The sample of the product that is directed through the bypass section is collected by an operator and is allowed to cool. The operator manually supplies the portion of the cooled sampled product to a spectrophotometer where the color is measured. This process of color measurement and identification is time consuming and, therefore, increases the manufacturing time of the product which in turn increase the costs associated with manufacturing.
Therefore, there is a desire for an optical color sensor that provides in situ color measurement of a cooled product that automatically takes a sample of the product, expedites sample cool time and provides information relating to the product for analysis.
In one exemplary embodiment, an on-line color sensor is provided for supplying light to a spectrophotometer that measures the color of cooled product. The product is extruded from a main extruder having a bypass section. The on-line color sensor comprises a housing having a top portion proximate to the bypass section and having an open bottom. The housing, the top portion and the open bottom define an internal portion. A funnel is positioned in the top portion and directs product from the bypass section into the interior portion of the housing. A cover hinge is connected to a top cover, a bottom cover and the housing. The cover hinge is used when the top and bottom cover are moved to at least a first position where the top cover covers the top portion and the funnel and where the bottom cover encloses the open bottom of the housing. A receptacle is connected to the housing and positioned in the interior portion proximate to the funnel portion. The receptacle holds the product received from the bypass section, and the product is allowed to cool while being held by the receptacle. A light source is connected to the top cover and provides light through the funnel into the interior portion of the housing. A light receiver is connected to the top cover, or the bottom cover, and the spectrophotometer. The light receiver captures light from the light source in the interior portion that is affected by the cooled product being held on the receptacle. The captured light is supplied to the spectrophotometer and is used to measure the color of the cooled product in the interior portion of the housing.